Announcement (2017-05-07): www.ruby-forum.com is now read-only since I
unfortunately do not have the time to support and maintain the forum any
more. Please see rubyonrails.org/community and ruby-lang.org/en/community
for other Rails- und Ruby-related community platforms.

I have a site with previously loaded images at various height and
widths, I changed what I wanted the height and width to be in my model
but the images have not been re-sized according to my specification.
How do I get them to be regenerate to the newly specified size?
My model code:
"class Image < Doc
file_column :file, :magick => {:image_required => true, :max_width =>
"800", :max_height => "2000", :versions => {:thumb => {:size =>
"300x300!"}, :mini => {:size => "200x200!"}}}
validates_file_format_of :file, :in => ["gif", "png", "jpg"],
:message => "has to be gif, png, or jpg."
end"